Fireplace contained air circulating heater



P. H. SROAT Odt. 4, 19.38.-

FIREPLACE CONTAINED AIR CIRCULATING HEATER 2 Sheets-Sheet 1 Filed Oct. 19, 1936 P. H. SROAT FIREPLACE CONTAINED AIR CIRCULATING HEATER 2 Sheets$heet 2 Filed Oct. 19, 1936 Patented Oct. 4, 1938 UNITED. STATES PATEN orFIcE FIREPLACE CONTAINED AIR CIRCULATING HEATER Paul H..Sroat, Portland, reg., as'signor to Heat- Rite Fireplace, Inc., Portland, 0reg., a corporation of Oregon Application October 19, 1936, Serial No. 106,420

9 Claims.

The principal object of this invention is to provide a fireplace heater which is self-contained which is susceptible of being easily installedto operate in and to be removed from a standard fireplace opening. My invention is., designedto fit substantially all standard size fireplace openings without alteration. To this end, I providea firebox and an air jacket surrounding saidfirebox thru which air is drawn by thermal action.

.A face plate is provided on the forward face of said device which face plateextends laterally from and about the marginal edges, of the fireplace opening. Said face plate j is sufficiently large that it will overlie the marginsof the large standard fireplace openings while the firebox and its surrounding casing'or jacket are sufficiently small to be received in the-mouth of theysmall fireplace openings. A further object of my a heating device of this character which may be supportedupon its forward edge with itscenter of mass arranged rearwardlythereof a substantial distance. The face plate of said device'is adapted to bear upon .thefront of the fireplace about the margins of the fireplace openingand the center of mass of said uni t is so placed thatit will tend to hold the face plate tightly against the front of said fireplac l.

A further object of myinvention is to provide.

the margins of saidface plate with a sealing element of such character that it will resiliently accommodate the irregularity to the frontsof fireplaces and will tend to'be compressed bythe off balance of said center of :mass. The placement of mass will hold said face plate with said sealing element extending about the margin thereof against. the front of the fireplace so that said'face plate is tightly sealed therewith.

A further object of my invention is to provide a fireplace heater of this character with an air vent so disposed as to receive the maximum radiated heat from the firebox and thus produce efficiency in said device. To this end I provide the firebox of said device with two laterally spaced flues and provide the casing or air jacket with a centrallydisposed vent extending upwardly between said flues and over the roof of said firebox. Thus the heat is radiated from the sides of the fiues .and the top of the firebox and heated air is discharged outwardly into a room thru a discharge aperture extending substantially the entire width of said firebox. To induce a more rapid flow of air thru said vents flue gas driven fans are arranged in said two flues and upon a shaft common to said flue fans, is a circulating invention is to, provide the line .5- in Fig. 4;

V away'from said face plate.

proved fireplace heater illustrating diagrammatically how it will fit into a numberof different sizes of fireplace openings;

Fig, ,3 is a perspective view of the firebox and the air jacket portions of my deviceshown separated, portions of the air jacket being shown broken away to disclose details of construction thereof;

Fig. 4 is an elevation of a fireplace with my improved heater shown seated therein;

Fig. 5 is a sectional view therethru taken on Fig. .6 is'a vertical section thru said device taken on the line 6 6 inFig. '7;

Fig. 7 isatransverse vertical section taken 'thru' said device on the line. l! in Fig. 6;

Fig. 7a is a sectional detail of construction; and

f,Fig. 8 is a horizontal section taken on the line 8-8 in Fig. 6.

. My improved fireplace heater comprises a selfcontained structure including a firebox member a, 'an air heating jacket b surrounding, but spaced 'from said firebox; memben'and a face plate 0.

Said face plate extends across the space between the airheating jacket and the firebox member andis sealed tightly about the margin of the open mouth of said firebox member. A sealing "ring d is arranged internally of an inturned flange 0- on the face plate and between them, a recess is defined for receiving the forward edge of'the firebox member, holding said. firebox member tightly in place in said face plate. Said ring,

flange and the forward edge of the firebox member may be bolted, welded or otherwise secured in place to form a strong rigid structure.

' The'marg'inal edges of the air heating jacket also terminate in a laterally projecting flange b, extending outwardly from said jacket and parallel to but spaced from the face plate. The extreme edge of said flange terminates in a later ally projecting marginal flange b2, extending The face plate also has a marginal flange 02 extending parallel to lil but spaced from the marginal flange 122. Underlying the space thus formed is a marginal angle element e preferably welded or otherwise secured to the face plate and to the flange of the jacket and a square recess is thus formed facing towards the front f of the masonry fireplace f. In said recess I preferably provide a resilient sealing element 9 of generous cross section composed preferably of material similar to resilient fabric, corded asbestos or sponge rubber. Normally said sealing element extends outwardly from the recess and is compressed into said recess only under the influence of a substantial pressure.

As is indicated in Fig. 1, the center of mass of said self-contained heater is arranged at the point marked X in said figure. Thus it extends rearwardly a substantial distance behind the face plate. Said heating device is supported in a fireplace opening 2 only along the bottom of the face plate. Thus, the off balance mass tends to tip the fireplace heater more deeply into the fireplace opening than to which it is set. It is resisted in said tipping by the engagement of the marginal edges of the face plate 6 with the front of the fireplace. Said tipping effect of the mass of said heater tends to compress the sealing element 9 and said sealing element tends to prevent said heating device from marring the highly finished front of a fireplace. Most fireplace fronts are made of brick or tile and their joints present an uneven surface. The resiliency of the sealing element tends to cause it to move into the irregularities to give the fireplace front the effect of being solidly and exactly fitted along the entire fireplace front. Said sealing element g also has its function of sealing to prevent the flue gases from passing upwardly between the face of the fireplace heater and the front of the fireplace.

The firebox member is closed top, bottom, at each side and in the back. The front is open into a room to be heated. I preferably provide a pair of flues h extending upwardly from the sides of the interior of the firebox. These are arranged as far towards the side as is possible to leave a space 712 between them. Lying in said space is a cupped recess h3 which fits more or less closely about the path described by the tips of the blades of a circulating fan 2' seated therein.

The floor a of the firebox member is provided with draft apertures a2 preferably arranged only along the forward edge thereof. I preferably arrange a grate a or fuel container in said firebox with the forward edge just inside said draft apertures. Thus, fuel located in said grate is permitted to burn with the air flowing inwardly thru the mouth of the firebox member and supplemented by the air flowing upwardly thru the said draft apertures a2 in the floor or the firebox member.

Underlying the apertures in the bottom of the fire-box is a retractable tray q constituting an ash receiver. Said tray is reciprocally mounted between two opposed slides 1'. When the tray is seated tightly against the front of the face plate it effectively prevents air for supporting combustion from flowing upwardly thru the apertures a2. If said tray is withdrawn slightly, an auxiliary draft is provided for increasing the flow of air upwardly thru said apertures.

In Fig. 5 the flow of flue gases is diagrammatically illustrated. In each of said flues h is a fan 70. Said fans are substantially larger in diameter than the circulating fan 2 located in the chamber between the air heating jacket and the firebox member. The fans k are housed within a rounded portion M in each of the flues. The two flue fans k and the circulating fan i are carried by a common shaft Z. The flue fans are positioned and arranged, as is shown in Figure 5, so that the ascending flue gases strike the blades of the fan and tend to rotate them. This gives rotation to the circulating fan i to produce forced draft of heated air, as will hereinafter be described.

The passageway for air to be heated is located between the exterior of the firebox member a and the interior of the air heating jacket 1). Arranged inwardly of said jacket is a heat reflector m of curved shape and preferably having a highly polished surface. I preferably make said heat reflector of stainless steel or similar material and find that said device improves the efficiency of the heater. Said heat reflector extends from adjacent the floor of the air heating jacket up the back thereof and along the roof overlying the firebox, but spaced therefrom. The space 722 be tween the flues forms a vent underlying the heat reflector, overlying the top of the firebox, and closed at the sides by the opposed faces of the flues. I have observed that the point of greatest heat is located here and the air flowing across the top of the firebox thru said vent is heated to the greatest degree. To obtain forced draft along said vent, the circulating fan i extends across the entire width of said vent but not the heighth thereof. Said fan serves to increase the quantity and rate of flow of air thru said vent substantially. That is, the rise in heat thru the passageway inside of the jacket due to progressively greater heat in the upper portions of said jacket produces a thermal flow of air which is supplemented by the driven-fan.

Two intake apertures n extend plate at the sides of the firebox opening. Said apertures preferably are covered by grill work or louvers. The air flowing therethru passes along the side of the firebox within the air heating jacket and then passes inwardly over the back and top of said firebox member thru the vent previously described. A discharge aperture 0 extends substantially across the entire face plate over the -firebox opening. As can be seen in Figures I and '7 most clearly, the face plate is cupped so as to extend outwardly from its point of joinder with the flange b of the jacket. Thus, lying between said face plate and said flange c is a marginal auxiliary chamber 1) into which the intake apertures n open and from which the discharge apertures permit the heated air to flow.

As is diagrammatically illustrated in Figure 2, my improved fireplace heater is adapted to be mounted in fireplace openings differing substantially in width and heighth. As is shown in dotted lines, said fireplace heater can be arranged in fireplace openings varying in width from 2 to .22 and in height from y to y2. This is effected thru the face by the relatively large difference in size of the air heating jacket of my device with respect to the marginal dimensions of the face plate thereof. It is usual to have a substantial area about the front of a fireplace below the mantle f3 thereof and between the sides f4 thereof. Thus, it is relatively unimportant how far over the marginal edges of the face plate overlies the marginal edges of the fireplace opening because of the fact that my device is arranged with its mass off center. Thus, the marginal edges of the face plate will be held tightly in place independent 2,1333'763 of auxiliary securing'devices: "I'he sealing elecirculating type which can be arranged in the fireplace out of the room proper and which will be capable of producing circulating heat with surprising efficiency. The flues are arranged to aline with the chimney f5 of the fireplace f.

I claim:

1. A heater adapted to seat in a fireplace opening,comprising a self-contained removable unit including an open mouthed firebox, an air heating jacket surrounding and spaced from said firebox and a face plate extending across the mouth of said casing and seated about the open mouth of said firebox and joiningsaid parts together, the whole of said heater unit lying rearwardly of said face plate, the firebox lying substantially entirely within the firebox opening and the mass of said unit being supported adjacent the plane of said face plate and the center of mass of said unit lying substantially rearwardly of said plane, whereby said disposition of mass exerts a substantial tipping moment about said support to tend to cause said face plate to bear tightly against the front of the fireplace.

2. A heater adapted to seat in a fireplace opening, comprising a self-contained removable unit including an open-mouthed firebox, an air heating jacket surrounding and spaced from said firebox and a face plate extending across the mouth of said casing and seated about the open mouth of said firebox and joining said parts together, the whole of said heater unit lying rearwardly of said face plate, the firebox lying substantially entirely within the firebox opening and the mass of said unit being supported adjacent the plane of said face plate and the center of mass of said unit lying substantially rearwardly of said plane, whereby said disposition of mass exerts a substantial tipping moment about said support to tend to cause said face plate to bear tightly against the front of the fireplace, a sealing member extending about the face plate and adapted to seat against the fireplace front under said tipping force,

3. A heater adapted to seat in a fireplace opening, comprising a self-contained removable unit including an open-mouthed firebox, an air heating jacket surrounding and. spaced from said firebox and a face plateextending across the mouth of said casing and seated about the open mouth of said firebox and joining said parts together, the whole of said heater unit lying rearwardly of said face plate, the firebox lying substantially entirely within the firebox opening and the mass of said unit being supported adjacent the'plane of said face plate and the center of mass of said unit lying substantially rearwardly of said plane, whereby said disposition of mass exerts a substantial tipping moment about said support to tend to cause said face plate to bear tightly against the front of the fireplace, a resilient sealing memberextending about the faceplate, and adapted to seat against the fireplace front and to be compressed by said tipping force.

'4. A heater adapted to seat in a fireplace opening, comprising a self-contained removable unit including an open'niouth'ed firebox, an air heating jacket surrounding and spaced from said firebox and a faceplate extending across the mouth of said casing and seated about the open mouth "of said firebox and-joining said parts together,

saidface" plate having an intake aperture" and an exhaust aperture overlying the intake aperture, both apertures extending into said jacket, said face plate provided with laterally projecting flange portions adapted to extend beyond the margins of said fireplace opening and to seat against the front of said fireplace, the whole of said heater unit lying rearwardly of said face plate, the firebox lying substantially entirely within the firebox opening and the mass of said unit being supported adjacent the plane of said face plate and the center of mass of said unit lying substantially rearwardly of said plane, whereby said disposition of mass exerts a substantial tipping moment about said support to tend to cause said face plate to bear tightly against the front of the fireplace and a sealing member extending about the face plate and adapted to seat against the fireplace front under said tipping force.

5. In a fireplace of the circulator type, a firebox having a flue extending upwardly, an air heating jacket extending about said firebox including an upwardly projecting vent extending over the top of said firebox and alongside said flue, an intake aperture entering the jacket at the bottom and a discharge aperture communicating with the top thereof, and a curved heat reflector element arranged in said jacket spaced from but facing said firebox, said reflector extending into and overlying said vent.

6. In a fireplace of the circulator type, a firebox municating with the top thereof. 7

'7. In a fireplace of the circulator type a firebox having a flue extending upwardly, an air heating jacket extending about said firebox including an upwardly projecting vent extending over the top of said firebox and alongside said flue, fan members'located upon a common shaft, one extending across said vent and another across said flue, said flue fan positioned to be rotated by the gases passing up said flue and to correspondingly rotate the vent fan to tend to force the movement of air thru the ventfan intake aperture entering the jacket at the bottom'and a discharge aperture communicating with the top thereof.

8. In a fireplace of the circulator type a firebox having a pair of laterally spaced flues extending upwardly, an air heating jacket extending about said firebox including an upwardly projecting vent extending over the top of said firebox and between the flues therefor, fan members located upon a common shaft, one extending across said vent and another across each of said flues, said flue fans positioned to be rotated by the gases passing up said flues and to correspondingly rotate the vent fans to tend to force the movement of air thru the vent, an intake aperture entering the jacket at the bottom and a discharge aperture communicating with the top thereof.

9. In a fireplace of the circulator type a firebox having a flue extending upwardly, an air heating jacket extending about said firebox including an upwardly projecting vent extending over the top of said firebox and alongside said flue, an intake aperture entering the jacket at the bottom and a discharge aperture communicating with the top thereof, said discharge aper- .ture substantially overlying the full width of the 'firebox, and a curved heat reflector element arranged in said jacket spaced from but facing said firebox, said reflector extending into and overlying said vent.

PAUL H. SROAT. 

